How do I make hair collide with a mesh?
You can't just turn on collision on the object and expect it to work.

Here is how u do it: first of all create your hair particle system.

Next turn on Hair Dynamics and turn on collision on the object.
Now go to the mesh with collision on and turn up the "soft body and cloth" outer and inner paramaters to say around 5 for both.

Now you can go back to the hair and turn up the steps to about 40 in the Dynamics tab. Now you should have good collision without the other nonsense. Also be careful when changing the other paramaters, it can slow everthing down tremendously.